(a) Field of the Invention
The present invention relates to a system for testing a flat panel display and method thereof. More particularly, the present invention relates to a system for testing a flat panel display and method thereof capable of determining a defect or inferiority for the respective pixels by analyzing a spectrum which respectively passes through a plurality of pixels periodically arranged on the flat panel display.
(b) Description of the Related Art
Generally, a flat panel display may include a liquid crystal display (LCD), a plasma display device (PDP), an organic electroluminescence display device (OLED), and a field emission display (FED). The liquid crystal display has been most actively researched because it has a high resolution and it has an enough fast response speed to realize a motion picture. The liquid crystal display includes a color filter display panel having a common electrode and a color filter or the like formed thereon, a thin film transistor display panel having a pixel electrode and a thin film transistor or the like formed thereon, a liquid crystal material injected between the color filter display panel and a thin film transistor display panel. The liquid crystal molecules having a dielectric anisotropy are rotated according to an electric field applied between the common electrode and the pixel electrode. Accordingly, an image information voltage applied to the pixel electrode is controlled while a predetermined voltage is applied to the common electrode, and then the liquid crystal molecules may transmit light or block light for the respective pixels thereby displaying a character or an image. The color filter display panel and the thin film transistor display panel are assembled in a vacuum and then the assembled are cut as a unit panel. Such a unit panel is called as “a display panel assembly.” In order to test the display panel assembly, a probe is respectively connected on the common electrode of the color filter display panel and the pixel electrode of the thin film transistor display panel and a driving signal is applied between the common electrode and the pixel electrode so that a test pattern is displayed on the display panel assembly, and then the defect or inferiority of the displayed test pattern is checked. Conventionally, the defect or the inferiority of the flat panel display is tested by observing an image displayed on the flat panel display using a naked eye or a microscope. However, such a testing method using the naked eye or the microscope may have drawbacks in that it requires a lot of times and labor as well as a yield difference may be occurred because a detector subjectively determines the defect or the inferiority. In addition, an automatic testing method using a television camera and an image processing technology has been well used. However, It has drawbacks in that it is expensive because it needs a high resolution and a high density television camera having a higher pixel density than that of the panel, the captured image is again observed by the naked eye so as to detect the defect or the inferiority on the flat display panel substrate. In addition, the testing methods using the naked eye, the microscope, or the conventional automatic testing apparatus has a limit of resolution, and accordingly, it cannot detect a fine smear or fine panel thickness inferiority. The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.